Such a grinding apparatus is already known, as disclosed, for example, in Patent Document 1.
[Patent Document 1]
                Japanese Patent Application Laid-open No. 9-300193        
A grinding flash and a grinding trace remain on a work ground by a rotary grindstone. Therefore, it is a conventional practice that the ground work is subjected to a treatment in an exclusive deflashing device and an exclusive polishing device, where the removal of a ground flash and the polishing of a ground surface are carried out. In such a method, however, a lot of labor is required for shifting the work from the grinding apparatus to the deflashing device or the polishing device, and, an equipment cost is high due to the need for the exclusive deflashing and polishing devices. For this reason, it is difficult to reduce the work-grinding cost.